Influence of fly ash and charcoal on the inducer activity of benzo[a]pyrene and smoke condensate in the gut mucosa of the rat.

Fly ash from either peat- or coal-fired power plants is unable to block the inducer activity of benzo[a]pyrene in the gastrointestinal tract. Activated charcoal retains adsorbed polycyclic aromatic hydrocarbons during passage through the gut so that no induction of polysubstrate monooxygenase occurs in the mucosa.